Installation Guide
Bonding Liner on Vertical and Inverted Way Faces
Vertical and overhead way faces behave differently from a horizontal slide, because gravity works against the glue line instead of holding the strip down. This guide covers the practical changes: thinner material, mechanical support, controlled cure and a different acceptance check.
The short answer: on a vertical or overhead face the liner no longer rests on the way. It has to be held until the adhesive can carry its own weight, and the adhesive has to stay where it was placed instead of running. Three changes follow before anything is mixed: use the thinnest strip that still covers the wear, support the strip mechanically rather than with clamp pressure, and keep the part still until full cure rather than until the mix feels hard.
Why a vertical face fails differently
On a horizontal way gravity presses the liner into the adhesive, so the main risk is a starved glue line. On a vertical face the load path reverses. The strip wants to slide, the adhesive wants to slump, and side clamp pressure squeezes material out of the top edge while leaving the bottom light. The joint ends thin at the top, thick at the bottom, and creeping for days. On an inverted face the strip hangs, so the film at the crown carries the weight in peel rather than shear.
Pick the thinnest strip that covers the wear
On a horizontal slide, thickness is mostly a machining allowance decision. On a vertical face it also sets how much mass the adhesive carries and how much peel the edges see. A 3.2 mm strip on a tall face is a different job from 0.8 mm: more weight, a larger moment at the top edge, more adhesive to fill. Where the wear allows, step down a grade and take the difference in machining.
Support the strip without starving the joint
The instinct is to clamp hard, and that is what most workshops get wrong. Clamps on a vertical face are awkward and rarely even. What the strip needs is support, not force.
- Shaped cauls that follow the face, held by wedges or props off a solid part of the machine, so pressure is perpendicular to the face.
- Reference stops at the bottom edge, so downward movement shows as a gap against a hard stop rather than disappearing into the adhesive.
- Screws through sacrificial tabs where the drawing allows, so the tab is machined away and no hole reaches the finished way.
Apply the adhesive as beads or ribs and let contact pressure spread them, rather than troweling it flat. A flat film on a vertical face runs as soon as it is worked and traps air with nowhere to go. Ribs collapse into a more even film and push air toward the edges. Control bond-line thickness with shims at the stops, not by wedge force.
Cure time is a positioning problem
Datasheets give a handling strength and a full cure at a stated temperature. On a vertical face the gap between them is the risky window: the joint may hold under light handling while still unable to carry the liner in shear. Leave support and stops until full cure at the workshop temperature actually present. Rotating a member to make the next operation easier is the commonest way a good vertical bond is ruined.
Inverted faces need a cradle, not a clamp
On an overhead face the liner hangs, so support has to come from below and cover the strip rather than press at a few points. A cradle or a shaped board with soft facing, held by props, spreads the load and keeps the adhesive in compression. Plan two things before opening the adhesive: where the runoff will go, so drips miss machined surfaces and oil holes, and how the cradle comes off without levering against the fresh edge.
Checking a vertical or inverted bond
| Check | How to do it | What a pass looks like |
|---|---|---|
| Movement | Mark the strip against the face before cure; measure after fixtures come off | No measurable shift against the stop |
| Glue line | Inspect both exposed edges with a light | Continuous film, no voids, no thick ridge at the bottom |
| Edge lift | Press the top and side edges with a blunt probe | No movement and no change in sound |
| Tap test | Tap along the strip at even spacing | Consistent tone; dull patches investigated first |
| Thickness | Measure strip plus glue line at several points | Within the planned machining allowance |
Record the marks and readings before machining, because once the strip is cut the evidence of movement is gone. If a patch fails the tap test, investigate rather than machining over it: a void under a vertical bond usually grows. The signatures are the same as for horizontal work, set out in the bonding mistakes guide.
Frequently asked questions
Can a horizontal procedure be used on a vertical face?
Not unchanged. Adhesive, preparation and acceptance logic carry over, but support and cure control have to be rethought because gravity now pulls the strip away from the joint.
Is a thicker liner better for a worn vertical way?
Usually not. Thicker material adds weight and peel load at the top edge and needs a thicker bond line. Use the thinnest grade that still leaves allowance for the wear you measured.
What if one edge lifts after the fixtures come off?
Stop and diagnose before machining. Edge lift on a vertical face usually means the strip moved during cure or the glue line was starved, and re-bonding rarely holds.
Material for the job
For vertical work the blue grade in thinner options covers most saddle and column faces. Green and brown suit a rebuild record that must distinguish two machines, and brick red where colour is chosen for inspection visibility. Bonding uses two-part epoxy adhesive; the load a finished pair carries is covered in the liner pressure guide.
Send a photo of the face, its orientation, the measured wear and the strip size you plan to use. TEBAK will confirm the thickness that leaves a workable machining allowance.